The truth is joining a group with a title like this is meaningless. I mean no offence to the person that had the idea, I can see why you would want to do this. But people who are top CSGO players or at the top in most FPS games will pick this game up quickly. Of course knowing the map better and being used to the mechanics etc will be an advantage for the first people that get to play this game, but not for long.
What you're talking about kinda happened with The Culling I guess, but it's not because a conscious group was created, rather the gameplay where the right sequence of block, hit, shove - would win every fight so the people that memorised it first and were on top of every update stayed undefeated and drove others way through it. More the fault of the developers in my opinion.
You should see this group as a good thing if anything. Like minded competitive people. As someone who isn't part of the group, all it does for me is make me want to practise a lot so I can compete and compare myself to them. There's nothing wrong with that, competitiveness generally brings out the best in a game. Some bad things too of course, but nothing can ever stop that. Even if there was a strict no sub communities rule or something silly like that.